Tcl Source Code

    result[1] = Tcl_NewIntObj(count);
    result[2] = Tcl_NewListObj(count, remObjv);
    Tcl_SetObjResult(interp, Tcl_NewListObj(3, result));
    ckfree(remObjv);
    return TCL_OK;
}

/**
 * Test harness for command and variable resolvers.
 */

static int
InterpCmdResolver(
    Tcl_Interp *interp,
    const char *name,
    Tcl_Namespace *context,
    int flags,
    Tcl_Command *rPtr)
{

    Interp *iPtr = (Interp *) interp;
    CallFrame *varFramePtr = iPtr->varFramePtr;
    Proc *procPtr = (varFramePtr->isProcCallFrame & FRAME_IS_PROC) ?
            varFramePtr->procPtr : NULL;
    Namespace *ns2NsPtr = (Namespace *)

            Tcl_FindNamespace(interp, "::ns2", NULL, 0);

    if (procPtr && (procPtr->cmdPtr->nsPtr == iPtr->globalNsPtr
            || (ns2NsPtr && procPtr->cmdPtr->nsPtr == ns2NsPtr))) {
        const char *callingCmdName =
                Tcl_GetCommandName(interp, (Tcl_Command) procPtr->cmdPtr);

        if ((callingCmdName[0] == 'x') && (callingCmdName[1] == '\0')
                && (name[0] == 'z') && (name[1] == '\0')) {
            Tcl_Command sourceCmdPtr = Tcl_FindCommand(interp, "y", NULL,
                    TCL_GLOBAL_ONLY);

            if (sourceCmdPtr != NULL) {
                *rPtr = sourceCmdPtr;
                return TCL_OK;
            }
        }
    }
    return TCL_CONTINUE;
}

static int
InterpVarResolver(
    Tcl_Interp *interp,
    const char *name,
    Tcl_Namespace *context,
    int flags,
    Tcl_Var *rPtr)
{
    /*
     * Don't resolve the variable; use standard rules.
     */

    return TCL_CONTINUE;
}

typedef struct MyResolvedVarInfo {
    Tcl_ResolvedVarInfo vInfo;  /* This must be the first element. */
    Tcl_Var var;
    Tcl_Obj *nameObj;
} MyResolvedVarInfo;

static inline void
HashVarFree(
    Tcl_Var var)
{
    if (VarHashRefCount(var) < 2) {
        ckfree(var);
    } else {
        VarHashRefCount(var)--;
    }
}

static void
MyCompiledVarFree(
    Tcl_ResolvedVarInfo *vInfoPtr)
{
    MyResolvedVarInfo *resVarInfo = (MyResolvedVarInfo *) vInfoPtr;

    Tcl_DecrRefCount(resVarInfo->nameObj);
    if (resVarInfo->var) {
        HashVarFree(resVarInfo->var);
    }
    ckfree(vInfoPtr);
}

#define TclVarHashGetValue(hPtr) \
    ((Var *) ((char *)hPtr - TclOffset(VarInHash, entry)))

static Tcl_Var
MyCompiledVarFetch(
    Tcl_Interp *interp,
    Tcl_ResolvedVarInfo *vinfoPtr)
{
    MyResolvedVarInfo *resVarInfo = (MyResolvedVarInfo *) vinfoPtr;
    Tcl_Var var = resVarInfo->var;

    int isNewVar;
    Interp *iPtr = (Interp *) interp;
    Tcl_HashEntry *hPtr;

    if (var != NULL) {
        if (!(((Var *) var)->flags & VAR_DEAD_HASH)) {
            /*
             * The cached variable is valid, return it.
             */

            return var;
        }


        /*
         * The variable is not valid anymore. Clean it up.
         */

        HashVarFree(var);
    }


    hPtr = Tcl_CreateHashEntry((Tcl_HashTable *) &iPtr->globalNsPtr->varTable,
            (char *) resVarInfo->nameObj, &isNewVar);
    if (hPtr) {
        var = (Tcl_Var) TclVarHashGetValue(hPtr);
    } else {
        var = NULL;
    }
    resVarInfo->var = var;

    /*
     * Increment the reference counter to avoid ckfree() of the variable in
     * Tcl's FreeVarEntry(); for cleanup, we provide our own HashVarFree();
     */

    VarHashRefCount(var)++;
    return var;
}

static int
InterpCompiledVarResolver(
    Tcl_Interp *interp,
    const char *name,
    int length,
    Tcl_Namespace *context,
    Tcl_ResolvedVarInfo **rPtr)
{
    if (*name == 'T') {
 	MyResolvedVarInfo *resVarInfo = ckalloc(sizeof(MyResolvedVarInfo));

 	resVarInfo->vInfo.fetchProc = MyCompiledVarFetch;
 	resVarInfo->vInfo.deleteProc = MyCompiledVarFree;
 	resVarInfo->var = NULL;
 	resVarInfo->nameObj = Tcl_NewStringObj(name, -1);
 	Tcl_IncrRefCount(resVarInfo->nameObj);
 	*rPtr = &resVarInfo->vInfo;
 	return TCL_OK;
    }
    return TCL_CONTINUE;
}

static int
TestInterpResolversCmd(
    ClientData clientData,
    Tcl_Interp *interp,
    int objc,
    Tcl_Obj *const objv[])
{
    static const char *const table[] = {
        "down", "up", NULL
    };
    int idx;
#define RESOLVER_KEY "testInterpResolver"

    if (objc != 2) {
        Tcl_WrongNumArgs(interp, 1, objv, "up|down");
 	return TCL_ERROR;
    }
    if (Tcl_GetIndexFromObj(interp, objv[1], table, "operation", TCL_EXACT,
            &idx) != TCL_OK) {
        return TCL_ERROR;
    }
    switch (idx) {
    case 1: /* up */
        Tcl_AddInterpResolvers(interp, RESOLVER_KEY, InterpCmdResolver,
                InterpVarResolver, InterpCompiledVarResolver);
        break;
    case 0: /*down*/
        if (!Tcl_RemoveInterpResolvers(interp, RESOLVER_KEY)) {
            Tcl_AppendResult(interp, "could not remove the resolver scheme",
                    NULL);
            return TCL_ERROR;
        }




    }
    return TCL_OK;
}

/*
 * Local Variables:
 * mode: c
 * c-basic-offset: 4
 * fill-column: 78
 * tab-width: 8
 * indent-tabs-mode: nil
 * End:
 */